Fabrication of driver-fuel elements for EBR-II

A US perspective on fast reactor fuel fabrication technology and experience part I: metal fuels and assembly design

“…The fuel slugs were observed to shorten axially and expand radially, leading to an undesired loss in fuel reactivity in the reactor core and requiring compensation through control rod motion [33]. The texture effect was found to be rectified in a majority of the fuel elements (97.9% success rate) after heat treating the fuel elements at 660°C [34].…”

“…Atomics International also fabricated approximately 24,000 Mark-II fuel elements beginning in mid-1973 [34]. The process was nearly identical to that employed on the ANL-W Coldline, but similar to Aerojet Nuclear, the contractor experienced problems with the injection casting, leak detection, and closure welding of the end plug to the jacket.…”

“…The 'cold' 3 fuel casting was used to test the equipment design. The U-5Fs alloy represented the equilibrium alloy for the melt refining process to be used for reprocessing irradiated nuclear fuel [34]. The next fabrication campaign was done in a hot cell using reprocessed (melt refined) fuel as feedstock.…”

“…Chemical constituents of typical cladding materials are provided in Table 4. Rejection of cladding jackets was not uncommon during early rod fabrication designs as a result of inadequate inner-diameter discrepancies in the wire wrap and wire wrap weld to the tubing that resulted from operator error, material problems, or a combination of both, scratches, dents, pits, and/or spots on the jacket surface [34].…”

“…The closure welding process originally employed a capacitance discharge technique [13,34] that fused the entire top of the end plug to the fuel rod jacket resulting in a hemisphericshaped weld. Welding was carried out under flowing-Ar gas through the welding head.…”